On Tue, 06 Jul 2021 at 17:58, zwj <757634...@qq.com> wrote: > Hi all, > > When I read the source code file src/backend/access/transam/xloginsert.c, I > get something confused me. > In the function XLogSaveBufferForHint, the flags are always > REGBUF_FORCE_IMAGE which means it is always need backups. > Is it right? Why do not check the full_page_writes?
The documentation [1] says: ------------------------------------------------------------------------------ wal_log_hints (boolean) When this parameter is on, the PostgreSQL server writes the entire content of each disk page to WAL during the first modification of that page after a checkpoint, even for non-critical modifications of so-called hint bits. ------------------------------------------------------------------------------ Does that mean whether the full_page_writes enable or not, if the wal_log_hints enabled, we always write the entire content of each disk page to WAL? If I'm right, should we mention this in wal_log_hints? [1] https://www.postgresql.org/docs/current/runtime-config-wal.html -- Regrads, Japin Li. ChengDu WenWu Information Technology Co.,Ltd.
